OLD IDEAS die hard. For more than a century and a half, the medical and public health professions have Vigorously promoted smallpox vaccination. "Antivaccinator" became synonymous with anti-intellectual. Patients ask us, "I was vaccinated, my children were vaccinated, all my family have been vaccinated; why aren't you vaccinating my grandchildren?" We have dropped smallpox vaccination just when the media have been criticizing the medical profession for lack of attention to preventive medicine. Some patients, and indeed some of our medical colleagues, do not understand the rationale behind cessation of routine smallpox vaccination.

Where does smallpox come from? While most patients understand the concept of infection or contagiousness, they frequently have not thought in terms of the source or reservoir of infectious agents. Although smallpox virus can be found for a short time in scabs and bedding from patients, for practical purposes infection results only from contact with patients in the